Coral Recruits Surveys

Overview

The Coral Recruit dataset contains juvenile coral observations collected at UVS stations using standardized quadrat surveys. Each 50-meter transect includes ten 0.5 × 0.5 m quadrats, placed at fixed 5-meter intervals along the transect line, for a total surveyed area of 2.5 m² per station.

Data are stored in two tables:

  • uvs.recruits_stations — One row per station with metadata and summary metrics
  • uvs.recruits_observations — One row per recruit observation, including genus, size, and quadrat

All records are linked by ps_station_id. Taxonomic fields include accepted_name and accepted_aphia_id, standardized to the genus level.


Tables


Stations (uvs.recruits_stations)

This table stores metadata and summary metrics for each coral recruit survey station. Each row corresponds to a depth-stratified UVS site where coral recruits were surveyed using a series of ten 0.25 m² quadrats (total area = 2.5 m²). Fields include spatial context, survey effort, and total recruit counts and density.

Table 1: Schema for uvs.recruits_stations: metadata and summary metrics for coral recruit stations
Field Type Required Description
ps_station_id STRING true Unique station ID (ps_site_id_depth).
ps_site_id STRING true Foreign key to uvs.sites.
exp_id STRING true Expedition ID (ISO3_YEAR).
method STRING true Survey method (uvs).
protocol STRING true Survey protocol (coral_recruits).
divers STRING true Divers who conducted the recruit survey.
region STRING true Region name.
subregion STRING true Subregion name.
locality STRING false Optional local feature (e.g., reef, bay).
latitude FLOAT true Latitude of station (decimal degrees).
longitude FLOAT true Longitude of station (decimal degrees).
date DATE true Date of coral recruit survey.
time TIME true Start time of the survey.
depth_m FLOAT true Average station depth (m).
depth_strata STRING true Depth bin: supershallow, shallow, deep.
habitat STRING true Habitat type.
exposure STRING true Exposure type.
n_quadrats INTEGER true Number of quadrats surveyed (typically 10).
quadrat_area_m2 FLOAT true Area of each quadrat in m² (typically 0.25).
survey_area_m2 FLOAT true Total area surveyed (e.g., 2.5 m²).
total_count INTEGER false Total number of coral recruits recorded.
count_m2 FLOAT false Recruit density (individuals/m²).
notes STRING false Optional QA or field notes.

Observations (uvs.recruits_observations)

This table contains one row per juvenile coral colony observed within a quadrat. Records include genus-level identification, maximum diameter (cm), and quadrat number. All observations are linked to a survey station via ps_station_id.

Table 2: Schema for uvs.recruits_observations: coral recruit observations by quadrat
Field Type Required Description
obs_id STRING true Unique observation ID (e.g., FJI_2025_rec_JSD_0001).
ps_station_id STRING true Foreign key to uvs.recruits_stations.
diver STRING true Name of the diver who recorded the observation.
station_label STRING true Field-assigned stratum label (e.g., shallow, deep).
depth_m FLOAT true Recorded depth (m) at which the transect was conducted.
quadrat INTEGER true Quadrat number (1–10) at fixed intervals along the transect.
accepted_name STRING true Genus-level scientific name (Genus sp.) of the coral recruit.
accepted_aphia_id INTEGER true WoRMS AphiaID — foreign key to taxonomy.corals.
diameter_cm FLOAT true Maximum colony diameter (cm), measured in the field.
notes STRING false Optional comments or QA annotations.

Density (uvs.recruits_density)

This table contains station-level summaries of coral recruit density by taxon, derived from raw counts in replicate quadrats along UVS transects. Each row represents a unique combination of ps_station_id and coral taxon, with recruit density standardized to individuals per square meter.

Coral recruits are defined as juvenile colonies <5 cm in maximum diameter, recorded within 10 haphazardly placed 0.25 m² quadrats (total survey area = 2.5 m² per transect). Recruits are typically identified to genus, and the standardized accepted_name and accepted_aphia_id fields represent the minimum taxonomic resolution confidently assigned to each observation.

Taxonomic information is joined from taxonomy.corals, and all entries are linked to the parent survey station via ps_station_id.

Table 3: Schema for uvs.recruits_density_by_taxa: coral recruit density summaries by station and taxon
Field Type Required Description
ps_station_id STRING true Unique station ID (ps_site_id_depth).
accepted_name STRING true Standardized taxon name (typically genus).
accepted_aphia_id INTEGER true WoRMS AphiaID — foreign key to taxonomy.corals.
family STRING true Family of the coral taxon.
growth_form STRING false Typical growth form of the genus (e.g., branching, massive, encrusting).
region STRING true Region name.
subregion STRING true Subregion name.
locality STRING false Optional local feature (e.g., reef, bay, cove).
depth_m FLOAT true Mean depth (m) of the station.
depth_strata STRING true Depth bin: supershallow, shallow, or deep.
habitat STRING true Dominant habitat type at the station.
exposure STRING true Wave/wind exposure at the station.
total_count INTEGER false Total number of recruits observed across all quadrats.
density_m2 FLOAT false Recruit density (individuals/m²), standardized by total quadrat area (2.5 m²).